I've used front panniers only on my 54 cm (26") LHT before and it ran fine. There was a thread just like this on here a while back. It seems most people said 60% in the front and 40% in the back was good. I put fully loaded panniers on the front low-rider rack and tent, etc. on the rear. You could certainly feel the weight in the front but it didn't really hurt the handling.